The invention relates to an apparatus for electronic engine control with a performance check for the final ignition stage and comprising an electrical control circuit for controlling the final ignition stage and/or fuel injection as a function of engine parameters such as engine temperature, engine speed, and the like.
Electronic engine control systems are known which comprise a processor which controls the engine operation taking into account various engine parameters. In particular, the optimal fuel injection quantity and the optimal ignition timing are determined as a function of engine speed, engine temperature, position of the accelerator pedal, and consideration of the characteristic diagrams of the specific engine. In the known engine controls, the engine parameters listed above are determined by suitable sensors. The engine speed can be determined, e.g., at the camshaft, the engine temperature can be determined by a thermal element, and the position of the accelerator pedal can be determined by a distance sensor or indirectly by an angle pickup which determines the position, of the throttle valve. Such an engine control is known, e.g., from DE-OS 35 41 731.
In motor vehicles whose exhaust system is equipped with a catalyst, unburned fuel can reach the catalyst in a faulty final ignition stage and destroy it while releasing extraordinarily high heat energy. There is a danger not only of the catalyst being destroyed, but even that the vehicle may catch on fire.